Device and method for processing information, battery pack, and transmitting medium

ABSTRACT

Two battery packs are loaded into respective loading portions, and serve to deliver power to respective units of a personal computer through a port and are supplied with power through the port from an AC adapter connected to an AC power supply so that they are charged. Each lock portion serving as a loading mechanism includes a switch interlocking therewith. Output of the switch is delivered to a CPU serving as a mode control unit. The CPU controls a CPU serving as a switch control unit within the battery pack in correspondence with loading state of the battery pack inputted from the switch interlocking with the lock portion to switch operation mode of the battery pack. Thus, it is possible to prevent instantaneous cut-off of power supply at the time of removal of battery without allowing the apparatus to be complicated, and/or without allowing the cost to be high.

TECHNICAL FIELD

This invention relates to an information processing apparatus and aninformation processing method adapted for preventing instantaneouscut-off of power supply by removal (detachment) of battery pack, andrelates to a battery pack and a transmission medium adapted forrecognizing in advance that battery pack is removed to preventinstantaneous cut-off of power supply.

1. Background Art

FIG. 1 shows connection relationship between a personal computer 1 and abattery pack unit 2 for supplying power to the personal computer 1. Asshown in this figure, battery packs 2-1 and 2-2 are detachably loaded(fitted) into the personal computer 1 through the battery pack unit 2.

A selector (changeover) switch 3 for carrying out switching between thebattery pack 2-1 and the battery pack 2-2 is provided at the personalcomputer 1, and output of the battery pack 2-1 or the battery pack 2-2is delivered into the personal computer 1 through a port 5 from theselector switch 3. Further, a control unit 4 for detectinginsertion/removal of the battery pack 2-1 or 2-2 to control the selectorswitch 3 is provided at the personal computer 1. The selector switch 3is required to be switched at high speed in order to preventinstantaneous cut-off of power (supply) with respect to unexpectedinsertion or removal of the battery pack 2-1 or 2-2. Accordingly, highspeed characteristic is required also for the operation of the controlunit 4.

Meanwhile, in order to realize speed required for the operation of thecontrol unit 4, it is necessary to constitute the control unit 4 ashardware. In addition, it was necessary to provide dedicatedcommunication line for transmitting signal of removal, etc. at highspeed also between the battery pack 2-1 and the battery pack 2-2 so thatwhen one battery pack is removed, power is supplied from the otherbattery pack. Accordingly, there were the problems that the conventionalconfiguration of the battery pack unit 2 and the personal computer 1becomes complicated and the cost becomes high.

2. Disclosure of the Invention

An object of this invention is to prevent instantaneous cut-off ofsupply of power without allowing the apparatus to be complicated andwithout allowing its cost to be high even when one of plural batterypacks is removed.

To realize this, an information processing apparatus according to thisinvention is directed to an information processing apparatus in whichplural battery packs are loaded (fitted) as power supply (source) sothat they can be inserted or removed (detached), wherein there isprovided mode control means for setting operation mode of the batterypack on the basis of detection result of detector (detecting) means fordetecting the state where the battery pack is loaded (fitted).

In this case, the detector means interlocks with loading mechanism forloading (fitting) the battery pack, and serves to detect release stateof the loading mechanism before the battery pack is completely removed(detached).

Moreover, the detector means may mechanically detect release state ofthe loading mechanism with respect to the battery pack orelectoronically detect such release state.

Further, the battery pack comprises therewithin charge control switchmeans and discharge control switch means, whereby respective switchmeans are turned ON or OFF by control by the mode control means so thatswitching of the operation mode is carried out.

Further, the mode control means serves to allow the charge controlswitch means and the discharge control switch means to be both turned ONto thereby allow the battery pack to be in active mode, to allow onlythe discharge control switch means to be turned ON to thereby allow thebattery pack to be in passive mode, and to allow the charge controlswitch means and the discharge control switch means to be both turnedOFF to thereby allow the battery pack to be in shut mode.

Further, when the detector means detects release state of the loadingmechanism with respect to any one battery pack which is not in the shutmode of the battery packs, the mode control means allows the pluralbattery packs to be all in the passive mode.

Further, the mode control means executes, after waiting for time whenoperation mode of removed battery pack is changed (switched) from thepassive mode to the shut mode, mode change (alteration) of the batterypack or packs to be active after any one of the battery packs is removed(detached).

In addition, as another information processing apparatus, the detectormeans may be provided within the battery pack. In this case, when thedetector means of any one battery pack operative in modes except for theshut mode of the plural battery packs detects release state of theloading mechanism, the mode control means requests (requires) all thebattery packs so that their operation modes are changed into the passivemode.

In this instance, the mode control means executes, after waiting fortime when operation mode of the removed battery pack is changed from thepassive mode to the shut mode, mode change of battery pack or packs tobe active after any one of the battery packs is removed (detached).

When the detector means of battery pack in the shut mode of the pluralbattery packs detects release state of the loading mechanism, the modecontrol means does not all the battery packs to carry out mode change.

An information processing method according to this invention is directedto an information processing method for an information processingapparatus in which plural battery packs are loaded (fitted) as powersupply (source) so that they can be inserted or removed, the methodcomprising: a detection step of detecting the state where the batterypack is loaded; and a mode setting step of setting mode of the batterypack on the basis of the state detected at the detection step.

In this instance, at the detection step, a procedure is taken such thatdetection operation interlocks with operation of loading mechanism forloading (fitting) the battery pack to detect release state of theloading mechanism before the battery pack is completely removed.

A battery pack according to this invention is directed to a battery packincluding a secondary battery therewithin and adapted for supplyingpower to an electronic equipment, the battery pack comprising: detectormeans for detecting loading with respect to the elecronic equipment;discharge control switch means for controlling discharge operation withrespect to the electronic equipment; charge control switch means forcontrolling charge operation with respect to the secondary battery; andswitching control means operative on the basis of detection result fromthe detector means, the switching control means being adapted to allowthe charge control switch means and the discharge control switch meansto be both turned ON to thereby allow the batterty pack to be placed inactive mode, to allow only the discharge control switch means to beturned ON to thereby allow the battery pack to be placed in passivemode, and to allow the charge control switch means and the dischargecontrol switch means to be both turned OFF to thereby allow the batterypack to be placed in shut mode, whereby in the case where the detectormeans detects release state of the loading mechanism when the batterypack is in modes except for the shut mode, the switching control meansallows the discharge control switch means to be turned ON to allow thebattery pack to change to (shift) the passive mode.

In this case, in the case where the battery pack is in the shut mode,even when the detector means detects release state of the loadingmechanism, the switching control carries out no operation.

A transmission medium according to this invention is directed to atransmission medium where computer program is caused to undergotransmission, wherein the computer program is used in an informationprocessing apparatus in which plural battery packs are loaded as powersupply (source) so that they can be inserted or removed (detached), thecomputer program comprising: a detection step of detecting the statewhere the battery pack is loaded with respect to the informationprocessing apparatus; and a mode setting step of setting mode of thebattery pack on the basis of the state detected at the detection step.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing conventional connection relationshipbetween personal computer and battery packs.

FIG. 2 is a block diagram showing the configuration of personal computerto which this invention is applied.

FIG. 3 is a view showing electric configuration of battery packsconnected to the personal computer of FIG. 2.

FIG. 4A is a view for explaining active mode of modes of the batterypack.

FIG. 4B is a view for explaining passive mode of the modes of thebattery pack.

FIG. 4C is a view for explaining shut mode of the modes of the batterypack.

FIG. 5 is a flow chart for explaining mode control processing in thepersonal computer.

FIG. 6 is a block diagram showing another example of the configurationof personal computer and battery packs to which this invention isapplied.

FIG. 7 is a view showing electric configuration of the battery packsshown in FIG. 6.

BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 2 is a block diagram showing a personal computer 10 supplied withpower from battery packs 2-1, 2-2, which is the best mode for carryingout this invention. The two battery packs 2-1, 2-2 are respectivelyloaded into loading portions 14-1, 14-2 of a battery pack unit 13, anddelivers power to respective units of the personal computer 10 through aport 11 and are supplied with power through the port 11 from an ACadapter 16 connected to an AC power supply 15 so that they are charged.

In the battery pack unit 13, when the battery packs 2-1, 2-2 are loadedinto loading portions 14-1, 14-2, they are respectively locked by lockportions 17-1, 17-2. Namely, the lock portions 17-1, 17-2 serve asloading mechanisms for loading the battery packs 2-1, 2-2 into theloading portions 14-1, 14-2, respectively.

The lock portion 17-1 is adapted so that when the battery pack 2-1 isremoved (detached) from the loading portion 14-1, that lock portion isrotated so that it is located at the position indicated by broken linesin the figure with a shaft 17-1A being as center, while when the batterypack 2-1 is loaded thereinto, that lock portion is rotated so that it islocated at the position indicated by solid line in the figure.

Moreover, the lock portion 17-1 includes a switch 18-1 which is turnedOFF when that lock portion is rotated so that it is located at theposition of broken lines and is turned ON as the result of the fact thatthe switch is pressed by the battery pack 2-1 when that lock portion isrotated so that it is located at the position of solid line. Namely, theswitch 18-1 interlocks with the lock portion 17-1 serving as the loadingmechanism. It is to be noted that the switch 18-1 may be adapted so thatwhen that lock portion is rotated so that it is located at the positionof broken lines, that switch is turned ON, while when the lock portionis rotated so that it is located at the position of solid line, thatswitch is turned OFF. Output of the switch 18-1 is delivered to a CPU 12serving as mode control unit through a switch 9.

Similarly to the lock portion 17-1, the lock portion 17-2 is adapted sothat when the battery pack 2-2 is removed (unloaded) from the loadingportion 14-2, that lock portion is rotated with a shaft 17-2A being ascenter so that it is located at the position indicated by broken linesin the figure to allow a switch 18-2 to be turned OFF. In addition, whenthe battery pack 2-2 is loaded, that lock portion is rotated so that itis located at the position indicated by solid line in the figure toallow the switch 18-2 to be turned ON. This switch may be adapted sothat operations of ON and OFF are opposite to the above. Output of theswitch 18-2 is also delivered to the CPU 12 through the switch 9.

The CPU 12 serving as the mode control unit controls CPUs 36-1, 36-2shown in FIG. 3 serving as switch control units of the battery packs2-1, 2-2 through the port 11 in correspondence with detection resultrelating to removal (unloading) or loading of the battery packs 2-1, 2-2inputted through the switch 9 from the switches 18-1, 18-2 interlockingwith the lock portions 17-1, 17-2 to switch the operation mode (whichwill be described later) of the battery packs 2-1, 2-2.

The port 11 is adapted to deliver power inputted from the battery packs2-1, 2-2 or the AC adapter 16 to respective units of the personalcomputer 10, and to deliver power inputted from the AC adapter 16 to thebattery packs 2-1, 2-2.

The AC adapter 16 is adapted to convert AC power from the AC powersupply 15 into DC power to output it to the port 11.

The electric configuration of the battery packs 2-1, 2-2 will now bedescribed with reference to FIG. 3.

The battery pack 2-1 includes a terminal 21-3 adapted so that controlsignal CNT is inputted or outputted in addition to a power supplyterminal 21-1 of the +(plus) side and a power supply terminal 21-2 ofthe −(minus) side. At the personal computer 10 side, there are providedterminals 20-1 to 20-3 so that terminals 21-1 to 21-3 are connected whenthe battery pack 2-1 is loaded. The terminals 20-1 and 20-2 arerespectively connected to terminals 11-1 and 11-2 of the port 11. Inaddition, the terminal 20-3 is connected to a terminal 11-5 of the port11.

The battery pack 2-2 similarly includes terminals 21-4, 21-5 for powersupply and a terminal 21-6 for control signal input/output. At thepersonal computer 10 side, there are respectively provided terminals20-4 to 20-6 in correspondence with the terminals 21-4 to 21-6 of thebattery pack 2-2 side.

The power supply terminal 20-4 and the terminal 20-1 of the personalcomputer 10 side are commonly connected, and the terminal 20-5 and theterminal 20-2 are commonly connected. The signal input/output terminal20-6 is connected to a terminal 11-6 of the port 11.

The AC adapter 16 includes a terminal 21-7 adapted so that controlsignal is inputted or outputted in addition to a +(plus) side powersupply terminal 21-8 and a −(minus) side power supply terminal 21-9. Atthe personal computer 10 side, there are provided terminals 20-7 to 20-9so that terminals 21-7 to 21-9 are connected when the AC adapter 16 isloaded. As described above, the AC adapter 16 converts AC power from theAC power supply 15 into DC power to deliver it to the personal computer10 or the battery packs 2-1, 2-2.

At the port 11, there are provided terminals 11-3, 11-4. Power deliveredfrom the terminals 11-1, 11-2 is delivered to respective units of thepersonal computer 10 through these terminals 11-3, 11-4. Moreover, atthe port 11, a terminal 11-9 is provided. The CPU 12 serving as the modecontrol unit is connected to the terminal 11-9. The CPU 12 can output acontrol signal to the port 11 through this terminal 11-9, and candeliver control signals from the terminals 11-5 to 11-7 to respectivebattery packs 2-1, 2-2 and the AC adapter 16 and can be supplied withsignals in a manner opposite to the above.

The battery pack 2-1 includes a secondary battery 31-1 which ischargeable battery. Further, the +(plus) side terminal of the secondarybattery 31-1 is connected to the terminal 21-1 through a series circuitof a Field Effect Transistor (FET) 32C-1 serving as switch for chargecontrol and a FET 34D-1 serving as switch for discharge control. The FET32C-1 and 34D-1 respectively include parasitic diodes 33-1 and 35-1. The−(minus) side terminal of the secondary battery 31-1 is connected to theterminal 21-2 through a resistor 37-1 for current detection.

The battery pack 2-1 comprises a CPU 36-1 for controlling switchingoperation of the FET 32C-1 and the FET 34D-1 which respectively serve ascharge control and discharge control switches. The CPU 36-1 allows theFETs 32C-1, 34D-1 to be turned ON or OFF in correspondence with controlsignal delivered through the port 11 and terminal 21-3 from the CPU 12to protect the secondary battery 31-1.

Moreover, this CPU 36-1 detects voltage of both ends of the terminals21-1 and 21-2 and voltage of both ends of the secondary battery 31-1,and detects, from voltage of both ends of the resistor 37-1, currentflowing in the secondary battery 31-1 (resistor 37-1). Further, the CPU36-1 allows the FET 32C-1 or 34D-1 to be turned ON or OFF incorrespondence with values of voltage of the both ends of the terminals21-1, 21-2 and terminal voltage of the secondary battery 31-1 to protectthe secondary battery 31-1.

The battery pack 2-2 is also constituted in a manner similar to thebattery pack 2-1. Namely, the battery pack 2-2 includes a secondarybattery 31-2 which is chargeable battery. Further, the +(plus) sideterminal of the secondary battery 31-2 is connected to the terminal 21-4through a series circuit of a FET 32C-2 and a FET 34D-2. The FETs 32C-2,34D-2 respectively include parasitic diodes 33-2 and 35-2. The −(minus)side terminal of the secondary battery 31-2 is connected to the terminal21-5 through a resistor 37-2.

The battery pack 2-2 comprises a CPU 36-2 for controlling switchingoperation of the FET 32C-2 and the FET 34D-2. The CPU 36-2 allows theFET 32C-2, 34D-2 to be turned ON or OFF in correspondence with controlsignal delivered through the port 11 and the terminal 21-6 from the CPU12 to protect the secondary battery 31-2.

Moreover, this CPU 36-2 allows the FET 32C-2 or 34D-2 to be turned ON orOFF in correspondence with values of voltage of both ends of theterminal 21-4 and the terminal 21-5 and voltage of both ends of thesecondary battery 31-2 to protect the secondary battery 31-2.

The battery packs 2-1, 2-2 are placed in three operation modes asindicated below. Explanation will be given with reference to FIGS. 4A,4B and 4C in regard to the case where particularly only the battery pack2-1 is taken as example with respect to these three operation modes.These operation modes are defined by the state of ON/OFF of the chargecontrol switch FET 32C-1 and the discharge control switch 34D-1 whichare included within the battery pack 2-1. In FIG. 4, respective FETs areindicated as switch in model form.

Active mode is shown in FIG. 4A. In this active mode, the dischargecontrol switch 34D-1 and the charge control switch 32C-1 are caused tobe both turned ON. Accordingly, in this active mode, the secondarybattery 31-1 can carry out both discharge and charge operations.

Passive mode is shown in FIG. 4B. In this passive mode, the dischargecontrol switch 34D-1 is caused to be turned ON and the charge controlswitch 32C-1 is caused to be turned OFF. Accordingly, in this passivemode, the secondary battery 31-1 can carry out only discharge operation.

Shut mode is shown in FIG. 4C. In this shut mode, both the dischargecontrol switch 34D-1 and the charge control switch 32C-1 are caused tobe turned OFF. Accordingly, in this shut mode, the secondary battery31-1 cannot carry out both charge and discharge operations.

In the personal computer 10 in which the battery packs 2-1, 2-2 areconnected through the battery pack unit 13, as a method of dischargingthe battery packs 2-1, 2-2, there exist two kinds of dischargeoperations of series discharge in which after discharge of one of thebattery packs 2-1, 2-2 is completed, the other battery pack startsdischarge operation and parallel discharge in which both the batterypacks 2-1, 2-2 are discharged at the same time.

On the other hand, as a method of charging battery packs 2-1, 2-2, thereexist two kinds of charge operations of series charge in which aftercharge of one of the battery packs 2-1, 2-2 is completed, the otherbattery pack starts charge operation and parallel charge in which boththe battery packs 2-1, 2-2 are charged at the same time.

In the series discharge and the series charge, one of the battery packs2-1, 2-2 is in active mode, and the other battery pack is in shut mode.In the parallel discharge and the parallel charge, both the batterypacks 2-1, 2-2 are in active mode.

The merit in the series discharge is that one of battery packs 2-1, 2-2can be selected in dependency upon circumstances to carry out dischargeoperation. The merit of the series charge is that the time required forcharging only one of the battery packs 2-1, 2-2 is short as compared tothe case in the parallel charge.

The merit in the parallel discharge is that discharge time, i.e., thetime required for working the personal computer 10 is long as comparedto the case of the series discharge. The merit of the parallel charge isthat the time required for charging both the battery packs 2-1 and 2-2is short as compared to the case of the series charge.

Moreover, the demerit in the series discharge is that discharge time isshort as compared to the case of parallel discharge. The demerit of theseries charge is that the time required for charging both the batterypacks 2-1 and 2-2 is long as compared to the parallel charge.

The demerit in the parallel discharge is that discharge operations ofboth the battery packs 2-1 and 2-2 are completed at the same time. Thedemerit of the parallel charge is that the time required for chargingone of the battery packs 2-1, 2-2 is long as compared to the case of theseries charge.

In the personal computer 10 shown in FIGS. 2 and 3, in consideration ofthe merit and the demerit of the series discharge or charge and theparallel discharge or charge, user can arbitrarily select one of them.In more practical sense, it is possible to select seriescharge/discharge or parallel charge/discharge by picture on screen ofthe personal computer 10. In addition, it is possible to also selectbattery pack to be used by picture on screen.

Initially, the operation when user selects, through the picture onscreen, series discharge in which the battery pack 2-1 is dischargedthereafter to discharge the battery pack 2-2 will be described. The CPU36-1 of the battery pack 2-1 allows both the discharge control FET 34D-1and the charge control FET 32C-1 to be turned ON by control of the CPU12 of the personal computer 10 to place the battery pack 2-1 in theactive mode. On the other hand, the CPU 36-2 of the battery pack 2-2sets, by control of the CPU 12, the operation mode of the dischargecontrol FET 34D-1 and the charge control FET 32C-1 to the shut mode.Accordingly, the battery pack 2-1 carries out discharge operation andthe battery pack 2-2 does not carry out discharge operation.

When discharge operation from the battery pack 2-1 is continued andterminal voltage of the battery 31-1 gradually lowers with passing oftie, the CPU 12 displays, at the picture on screen, its voltage loweringinformation obtained through the CPU 36-1. In the case of the manualoperation, user confirms that picture on screen to switch discharge fromthe battery pack 2-1 to the battery pack 2-2. In addition, in the caseof the automatic operation, the CPU 12 may allow the CPU 36-2 to carryout discharge from the battery pack 2-2.

Also in either case, the CPU 36-1 of the battery pack 2-1 allows boththe discharge control FET 34D-1 and the charge control FET 32C-1 to beturned OFF by control of the CPU 12 to place the battery pack 2-1 in theshut mode. On the other hand, the CPU 36-2 of the battery pack 2-2 setsoperation mode of the discharge control FET 34D-2 and the charge controlFET 32C-2 to the active mode by control of the CPU 12. Accordingly, thebattery pack 2-2 carries out discharge operation, but the battery pack2-1 does not carry out discharge operation.

The operation when user selects, through the picture on screen, paralleldischarge in which the battery pack 2-1 of lower battery voltage and thebattery pack 2-2 of higher battery voltage are discharged in parallelwill be described below.

The CPU 12 of the personal computer 10 requests the CPUs 36-1, 36-2 ofthe respective battery packs 2-1, 2-2 to carry out detection of batteryvoltages of the respective batteries 31-1, 31-2.

The CPU 36-1 detects voltage of the secondary battery 31-1 incorrespondence with this request to notify its detection result to theCPU 12. Similarly, the CPU 36-2 detects voltage of the secondary battery31-2 to notify its detection result to the CPU 12.

The CPU 12 receives notification from the two battery packs 2-1 and 2-2in this way to detect that voltage of the secondary battery 31-2 of thebattery pack 2-2 is higher than that of the secondary battery 31-1 ofthe battery pack 2-1.

Then, the CPU 12 requests the CPU 36-1 to set the passive mode in whichthe FET 32C-1 of the battery pack 2-1 of lower terminal voltage isturned OFF and the FET 34D-1 thereof is turned ON. Further, the CPU 12requests the CPU 36-2 to set the active mode in which both the FET 32C-2and the FET 34D-2 of the battery pack 2-2 of higher voltage are turnedON. The CPU 36-2 allows both the FET 32C-2 and the FET 34D-2 to beturned ON in correspondence with this request to start discharge.

When the FETs 34D-2, 32C-2 of the battery pack 2-2 are both turned ON,discharge current from the secondary battery 31-2 of the battery pack2-2 is not interrupted (cut off) and charge current with respect to thesecondary battery 31-2 is not interrupted.

The battery pack 2-2 supplies power from the secondary battery 31-2 torespective units of the personal computer 10 via the secondary battery31-2, the FET 32C-2, the FET 34D-2, the terminals 21-4, 20-4, 11-1,11-3, 11-4, 11-2, 20-5, 21-5 and the resistor 37-2.

Since the secondary battery 31-2 supplies power, its terminal voltagegradually lowers with passing of time. On the contrary, since thebattery pack 2-1 does not carry out discharge operation, terminalvoltage of the secondary battery 31-1 hardly lowers and remains to beconstant voltage.

Meanwhile, voltage actually outputted from the battery pack 2-1 islowered by voltage drop of the parasitic diode 33-1 with respect toterminal voltage of the secondary battery 31-1. Thus, when outputvoltage of the secondary battery 31-2 and voltage outputted from thebattery pack 2-1 are substantially equal to each other, dischargecurrent flows from the battery pack 2-1. The CPU 36-1 detects dischargecurrent of this secondary battery 31-1 .

In this case, when discharge current flows in the state where thebattery pack 2-1 is in the passive mode, discharge current is passedthrough the parasitic diode 33-1 because the charge control FET 32C-1 isin OFF state. In order to eliminate loss of power by resistance of thisparasitic diode 33-1, the CPU 36-1 is operative so that when it isjudged that its discharge current is a predetermined reference value ormore, the CPU 36-1 allows the FET 32C-1 of the battery pack 2-1 to beturned ON, i.e., set the batter pack 2-1 so that it is placed in theactive mode.

By the above-mentioned processing, the secondary battery 31-2 and thesecondary battery 31-1 are connected in parallel and both carry outdischarge operation. For this reason, discharge current of the secondarybattery 31-2 is once greatly lowered and gradually rises thereafter.Moreover, discharge current of the secondary battery 31-1 once greatlyrises and gradually lowers thereafter.

Further, when discharge currents of the secondary battery 31-1 and thesecondary battery 31-2 are equal to each other, discharge current ofthat value is continued to flow thereafter. Terminal voltages of thesecondary battery 31-1 and the secondary battery 31-2 are substantiallyconstant, but gradually lower with passing of time.

In this case, the reason why when terminal voltages of the two batteriesare equal to each other, the battery pack 2-1 is caused to be in theactive mode is as follows. When the battery pack 2-1 is caused to be inactive mode in the state where terminal voltages of the both batteriesare different from each other, charge operation is carried out from thesecondary battery 31-2 of higher terminal voltage to the secondarybattery 31-1 of lower terminal voltage. In order to prevent suchoperation, the battery pack 2-1 is caused to be in the active mode.

Meanwhile, in the series discharge and the series charge, since only onebattery pack of two battery packs is used, there are instances whereuser may remove (detach) unused battery pack. In addition, there areinstances where user may erroneously remove the battery pack being used.Thus, instantaneous interruption (cut-off) of power supply would takeplace.

In view of the above, in the personal computer 10, both battery packsare caused to be in the passive mode before either battery is removed toprevent instantaneous cut-off of power supply. The operation of thepersonal computer 10 adapted for preventing instantaneous cut-off ofpower supply followed by unexpected removal (detachment) of the batterypack in the series discharge and the series charge will be describedbelow.

FIG. 5 shows a flow chart of mode control processing of the CPU 12serving as the mode control unit in the case where the battery pack 2-1is removed (detached) in the state of series discharge.

Initially, at step S1, the CPU 12 of the personal computer 10 sets theoperation mode of the battery packs 2-1, 2-2 to the series dischargemode. In more practical sense, the CPU 36-1 of the battery pack 2-1 iscaused to turn ON both the discharge control FET 34D-1 and the chargecontrol FET 32C-1 to set the battery pack 2-1 so that it is placed inthe active mode. On the other hand, the CPU 36-2 of the battery pack 2-2is caused to turn OFF both the discharge control FET 34D-2 and thecharge control FET 32C-2 to set the battery pack 2-2 so that it isplaced in the shut mode. For this reason, the battery pack 2-1 carriesout discharge operation and the battery pack 2-2 does not carry outdischarge operation.

Then, the CPU 12 judges whether or not the switch 18-1 or 18-2interlocking with lock portion 17-1 or 17-2 serving as the loadingmechanism is turned OFF. When user attempts to remove (detach) thebattery pack 2-1 being discharged, before the battery pack 2-1 loadedinto the loading portion 14-1 is removed, the lock portion 17-1 servingas the loading mechanism is rotated so that it is located at theposition indicated by broken lines in FIG. 2 with the shaft 17-1 A beingas center. At this time, the switch 18-1 interlocking therewith isturned OFF. That signal turns ON the switch 9. Thus, the CPU 12 isinformed that any lock portion is unlocked (detached). Therefore, atstep S2, the CPU 12 stands by (waits) until the switch 17-1 or 17-2 isturned OFF. When either switch is turned OFF, the processing operationproceeds to step S3.

At the step S3, the CPU 12 controls the CPU 36-1 to allow the chargecontrol FET 32C-1 to be turned OFF to set the battery pack 2-1 so thatit is placed in the passive mode. In addition, the CPU 12 controls theCPU 36-2 to allow the discharge control FET 34D-2 to be turned ON, andto allow the charge control FET 32C-2 to be turned OFF to set thebattery pack 2-2 so that it is placed in the passive mode.

Accordingly, since both the battery packs 2-1 and 2-2 are placed in thestate where their operation modes are set to the passive mode, any oneof higher output voltage of the battery packs 2-1, 2-2 connected inparallel carries out discharge operation. Even if the battery pack 2-1is removed (detached) in this state, since power is delivered from thebattery pack 2-2, instantaneous cut-off of power supplied does not takeplace.

A certain short time is required until user actually removes the batterypack 2-1 from the loading portion 14-1 after lock state by the lockportion 17-1 is released. For this time period, both the battery packs2-1 and 2-2 can be set so that they are placed in the passive mode. Inthis instance, the state where both battery packs 2-1, 2-2 are in thepassive mode is caused (assumed) to be removal mode. When the batterypacks 2-1, 2-2 are in the removal mode, even if any either one of themis removed, instantaneous cut-off of power supplied is substantiallyprevented.

Then, at step S4, the CPU 12 judges through the CPU of either batterypack whether or not the battery pack is removed. When the CPU 12 judgesthat the battery pack has been removed, the processing operationproceeds to step S5.

Then, at the step S5, the operation mode of the remaining battery packafter removal is set to the active mode (A mode). In this instance, itis necessary that time required for switching from the passive mode tothe active mode of the remaining battery pack is longer than timerequired when the removed battery pack is switched from the passive modeto the shut mode.

In more practical sense, after the removed battery pack 2-1 is switchedfrom the passive mode to the shut mode, the remaining battery pack 2-2is caused to be in the active mode. The reason why such an approach isemployed is to prevent erroneous operation as the result of the factthat the battery pack 2-1 once removed is loaded into the loadingportion 14-1 in the state where it is yet in the passive mode.

The operation that removed battery pack is switched from the passivemode to the shut mode is carried out by the following processing. Forexample, the CPU 36-1 of the battery pack 2-1 recognizes that thebattery pack 2-1 is removed by cut-off, etc. of communication linebetween the CPU 36-1 and the CPU 12 to allow the discharge control FET34D-1 to be turned OFF. Thus, since the charge control FET 32C-1 isalready turned OFF, shut mode can be set. In the shut mode, even whenthe battery pack is left in the state where the battery pack is removed(detached), no power is supplied to the power supply terminal.Accordingly, danger such as short circuit, etc. can be prevented. Inaddition, it can be prevented that large current erroneously flows inanother battery pack when the battery pack is next inserted.

It is to be noted that while, in the personal computer 10 shown in FIGS.2 and 3, the CPU 12 receives detection result from the switches 18-1 and18-2 through the switch 9 to place two battery packs in the removal modeeven if battery pack to be removed is particularly not known, the CPU 12may directly judge, from detection result from the switch 18-1 or 18-2,the battery pack to be removed.

FIG. 6 is a block diagram showing personal computer 10 supplied withpower from battery packs 19-1, 19-2, which is another best mode forcarrying out this invention. Two battery packs 19-1, 19-2 are loadedinto loading portions 14-1, 14-2 of a battery pack unit 19, and serve todeliver power to respective units of personal computer 10 through port11 and is supplied with power through the port 11 from AC adapter 16connected to AC power supply 15 so that they are charged.

In the battery pack unit 19, when the battery packs 19-1, 19-2 areloaded into the loading portions 14-1, 14-2, they are locked by lockportions 25-1, 25-2 serving as the loading mechanism.

The lock portion 25-1 is rotated with a shaft 25-1A being as center whenthe battery pack 19-1 is removed from the loading portion 14-1, and whenthe battery pack 19-1 is loaded thereinto.

Rotation of the lock portion 25-1, 25-2 can be detected by switches26-1, 26-2 provided in a manner interlocking with the lock portions 25-1and 25-2 within the battery packs 14-1, 14-2. Namely, in the batterypacks 19-1 and 19-2, loading state into the loading portions 14-1, 14-2can be detected by their own switches 26-1 and 26-2.

Outputs of the switches 26-1 and 26-2 of the battery packs 19-1 and 19-2are delivered from the port 11 to the CPU 12 through CPUs 36-1 and 36-2included therewithin.

As shown in FIG. 7, an electric switch 38-1 corresponding to the switch26-1 is provided within the battery pack 19-1. This electric switch 38-1is connected to the CPU 36-1.

Moreover, an electric switch 38-2 corresponding to the switch 26-2 isprovided within the battery pack 19-2. This electric switch 38-2 isconnected to the CPU 36-2.

In the battery packs 19-1 and 19-2 including respective switchestherewithin in order to recognize the loading state, switch 9 shown inFIGS. 2 and 3 at the personal computer 10 side becomes unnecessary.Namely, change at the personal computer 10 side becomes unnecessary. Inaddition, it is possible to inform to other battery pack through the CPU12 that the (corresponding) battery pack is removed to inform change(shift) to the removal mode.

The operation in the case where when series discharge is carried out inthe personal computer 10 shown in FIGS. 6 and 7, the battery pack 19-1is unexpectedly removed will be briefly described.

The CPU 36-1 of the battery pack 19-1 recognizes, by switch 26-1, thatthe lock portion 25-1 is rotated in the opening direction so thatloading is released (OFF of the switch 38-1 from an electric point ofview). Thus, the CPU 36-1 transmits the fact to the CPU 12.

By control of the CPU 12, the CPU 36-1 allows the charge control FET32C-1 to be turned OFF to set the battery pack 19-1 so that it is placedin the passive mode.

The CPU 36-2 of the battery pack 19-2 recognizes, through the CPU 12,that the battery pack 19-1 is removed to allow discharge control FET34D-2 to be turned ON and to allow charge control FET 32C-2 to be turnedOFF by control of the CPU 12 to set the battery pack 19-2 so that it isplaced in the passive mode.

Accordingly, since both the battery packs 19-1, 19-2 are placed in thestate where their operation modes are set to the passive mode, batterypack of higher output voltage of the battery packs 19-1, 19-2 connectedin parallel carries out discharge operation. Even if the battery pack19-1 is removed in this state, since power is delivered from the batterypack 19-2, instantaneous cut-off of power supplied does not take place.

In the more practical example shown in FIGS. 2 and 3, the operation forremoving the battery pack 2-1 being discharged has been described. Theoperation for removing the battery pack 2-2 which is not beingdischarged is as follows.

When user attempts to remove the battery pack 2-2, before the batterypack 2-2 loaded into the loading portion 14-2 is removed, the lockportion 17-2 is rotated with shaft 17-2A being as center so that it islocated at the position indicated by broken lines. At this time, theswitch 18-2 is turned OFF. That signal allows the switch 9 to be turnedON. Thus, the CPU 12 is informed that either one of lock portions isdetached.

The CPU 12 allows the battery packs 2-1 and 2-2 to be both in thepassive mode, i.e., the removal mode through the CPUs 36-1 and 36-2 ofthe battery packs 2-1 and 2-2.

Accordingly, since both the battery packs 2-1 and 2-2 are placed in thestate where their operation modes are set to the passive mode, batterypack of higher output voltage of battery packs 2-1, 2-2 connected inparallel carries out discharge operation. Even when the battery pack 2-2is removed (detached) in this state, since power is supplied from thebattery pack 2-1, instantaneous cut-off of power supplied does not takeplace.

In the personal computer 10 shown in FIGS. 6 and 7, it is possible todiscriminate, by the CPU 12, which battery pack is removed by user.Accordingly, when battery pack which is not being discharged is removed,there is no necessity to intentionally set the operation mode to theremoval mode.

Moreover, while switches 18-1, 18-2 or switches 26-1, 26-2 have beendescribed as mechanical switch, e.g., electronic switch, e.g., photodiode or non-contact switch, etc. may be employed.

Further, as the detector means, there may be employed detector meanscapable of detecting contact of finger with respect to the battery pack,e.g., by change of electrostatic capacitance, etc.

Further, while, as the loading mechanism of the battery pack, locksystem has been taken as example, there may be employed structure suchthat switch for detecting removal is operative at the initial or earlytime point of the removal operation so that switching to the removalmode is completed by the time when battery pack is actually removed likecover (door) member, or notch back, etc. Further, if push button iscaused to be of configuration interlocking with the loading mechanism,forgetting of pushing down of the switch, etc. can be also prevented.

Further, while the number of battery packs is 2 (two) in theabove-mentioned embodiments, if the number of battery packs is two ormore, an arbitrary number of battery packs may be employed. In addition,electronic equipment into which the battery pack is loaded may beelectronic equipments except for personal computer.

It is to be noted that computer program for carrying out the respectiveprocessing may be caused to undergo transmission to user through networktransmission medium such as Internet or digital satellite, etc. inaddition to transmission medium consisting of information recording(storage) medium such as magnetic disc or CD-ROM, etc.

As stated above, in accordance with this invention, such an approach isemployed to detect loading state of the battery to set mode of thebattery on the basis of its result. Accordingly, occurrence ofinstantaneous cut-off of power at the time of removal of battery can beprevented without allowing the apparatus to be complicated or allowingits cost to be high.

What is claimed is:
 1. An information processing apparatus in whichplural battery packs are loaded as power supply so that they can beinserted or removed, each battery pack having charge control switchmeans and discharge control switch means, the apparatus comprising: modecontrol means for setting operation mode of each battery pack on thebasis of a detection result of a detector means for detecting the statewhere the battery pack is loaded, the control means setting an activemode by turning ON the charge control switch means and turning ON saiddischarge control switch means, setting a passive mode by turning OFFthe charge control switch means and turning ON said discharge controlswitch means, and setting a shut mode by turning OFF the charge controlswitch means and turning OFF said discharge control switch means; andthe detector means interlocking with a loading mechanism for loading thebattery pack and detecting a release state of the loading mechanismbefore the battery pack is completely removed.
 2. An informationprocessing apparatus as set forth in claim 1, wherein when the detectormeans detects the release state of the loading mechanism with respect toany one battery pack which is not in the shut mode, the mode controlmeans switches all of the battery packs to the passive mode.
 3. Aninformation processing apparatus as set forth in claim 2, wherein when abattery pack is removed the mode control means waits for the operationmode of the removed battery pack to be switched from the passive mode tothe shut mode and then switches one or more of the remaining batterypack(s) to the active mode.
 4. An information processing method for aninformation processing apparatus in which plural battery packs areloaded as power supply so that they can be inserted or removed, themethod comprising the steps of: detecting whether or not a battery packis loaded, wherein an unloaded state is detected upon removal of thebattery pack by detecting a release state of the battery pack's loadingmechanism before the battery pack is removed; and setting a mode of thebattery pack on the basis of the state detected at the detection step.5. A battery pack including a secondary battery therewithin and adaptedfor supplying power to an electronic equipment, the battery packcomprising: detector means for detecting loading with respect to theelectronic equipment; discharge control switch means for controllingdischarge operation with respect to the electronic equipment; chargecontrol switch means for controlling charge operation with respect tothe secondary battery; and switching control means operative on thebasis of detection result from the detector means, the switching controlmeans being adapted to allow the charge control switch means and thedischarge control means to be both turned ON to thereby allow thebattery pack to be placed in active mode, to allow only the dischargecontrol switch means to be turned ON to thereby allow the battery packto be placed in passive mode, and to allow the charge control switchmeans and the discharge control switch means to be both turned OFF tothereby allow the battery pack to be placed in shut mode, whereby in thecase where the detector means detects release state of the loadingmechanism when the battery pack is in modes except for the shut mode,the switching control means allows the discharge control switch means tobe turned ON to change (shift) to the passive mode.
 6. A battery pack asset forth in claim 5, wherein in the case where the battery pack is inthe shut mode, even when the detector means detects release state of theloading mechanism, the switching control means carries out no operation.